Molekula
L-Cystine
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
L-Cystine is a disulfide-bonded dimer of the amino acid L-cysteine, used in biochemical research, cell culture media, and pharmaceutical formulations for its role in protein structure and antioxidant activity. In food manufacturing it serves as a flour treatment agent and dough strengthener, a flavoring agent and a nutritional supplement, and it is also used as a cosmetic ingredient. It has a CAS number of 56-89-3, molecular formula [-SCH2CH(NH2)CO2H]2, and a molecular weight of 240.30 g/mol. Stable at ambient storage conditions. Molekula supplies L-Cystine from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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100 g — $69.10 per pack
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1 kg — $206.90 per pack
Need a different quantity or pack?
Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | White crystals or crystalline powder |
| Specific rotation | -215° to -225° |
| Heavy metals | ≤ 0.0015% |
| Loss on Drying | ≤ 0.20% |
| Chloride (Cl-) | ≤ 0.10% |
| Assay | 98.5% to 101.5% |
| Residue on Ignition | ≤ 0.10% |
| Particle Size | Approx 80 mesh/ 165 micron. |
| Iron (Fe) | ≤ 0.003% |
| Arsenic (As) | ≤ 1.5ppm |
| Sulphates (SO4)(2-) | ≤ 0.040% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Melting Point | 260.5 °C |
| pKa | pKa = 1 |
Source: PubChem CID 67678 (Human Metabolome Database (HMDB), DrugBank)
Identification
| Property | Value |
|---|---|
| SKU | 11394887 |
| CAS Number | 56-89-3 |
| IUPAC Name | (2R)-2-amino-3-[[(2R)-2-amino-2-carboxyethyl]disulfanyl]propanoic acid |
| EC Number | 200-296-3 |
| Molecular Formula | [-SCH2CH(NH2)CO2H]2 |
| Molecular Weight | 240.30 |
| Exact Mass | 240.0238 |
| SMILES | C([C@@H](C(=O)O)N)SSC[C@@H](C(=O)O)N |
| InChIKey | LEVWYRKDKASIDU-IMJSIDKUSA-N |
| InChI | InChI=1S/C6H12N2O4S2/c7-3(5(9)10)1-13-14-2-4(8)6(11)12/h3-4H,1-2,7-8H2,(H,9,10)(H,11,12)/t3-,4-/m0/s1 |
| PubChem CID | 67678 |
| REACH Code | Y113 |
| TSCA Listed | Yes |
| HTS Code | 29309092 |
| Tariff Code | 2930901300 |
Safety & GHS
Detailed safety information available in the SDS — see Documents below.
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Russian, Spanish.
Certificate of Analysis (CoA) by batch
Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.
Synonyms
- 1-Cystine
- beta,beta'-Dithiodialanine
- Cysteine disulfide
- Cystin
- cystine
- Cystine acid
- Cystine, L-
- Dicysteine
- L-Cysteine disulfide
- L-Dicysteine
Frequently asked questions
What is L-Cystine used for?
L-Cystine is primarily used in pharmaceuticals, cosmetics, and dietary supplements for its role in protein synthesis and antioxidant properties.
What is the chemical formula and molecular weight of L-Cystine?
The formula is [-SCH2CH(NH2)CO2H]2 and the molecular weight is 240.30 g/mol.
How should L-Cystine be stored?
Store at ambient temperature, protected from moisture and light.
What grade of L-Cystine does Molekula supply?
Molekula supplies L-Cystine in pharmaceutical grade.
Can Molekula supply L-Cystine in bulk?
Yes, Molekula can supply L-Cystine in bulk quantities upon request.
What documentation comes with an order of L-Cystine?
Each order includes a Certificate of Analysis (CoA) and Safety Data Sheet (SDS).
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.